FDA Sets MONOFERRIC's Regulatory Review Period for Patent Term Extension

The Food and Drug Administration published a notice on October 9, 2026, determining the regulatory review period for MONOFERRIC (ferric derisomaltose) for purposes of patent term extension. FDA acted after Pharmacosmos Holding A/S applied to the Director of the U.S. Patent and Trademark Office for extension of a patent that claims that human drug product (91 Fed. Reg. 64660).

What FDA determined

Under 35 U.S.C. 156(g)(1)(B), FDA's determination of the length of a regulatory review period for a human drug product includes the testing phase and the approval phase. FDA determined that the applicable regulatory review period for MONOFERRIC is 3,292 days, of which 2,990 days occurred during the testing phase and 302 days during the approval phase. It derived those periods from three verified dates: an investigational new drug exemption under section 505(i) of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 355(i)) became effective on January 13, 2011; the new drug application (NDA 208171) was initially submitted on March 21, 2019; and NDA 208171 was approved on January 16, 2020 (91 Fed. Reg. 64661-62).

What the USPTO application seeks

The notice states that the USPTO received a patent term restoration application for MONOFERRIC covering U.S. Patent Nos. 8,815,301 and 10,414,831 from Pharmacosmos Holding A/S. In a letter dated October 7, 2025, FDA advised the USPTO that MONOFERRIC had undergone a regulatory review period and that its approval represented the first permitted commercial marketing or use of the product. The face of each patent is titled "Stable iron oligosaccharide compound." FDA's determination of the regulatory review period establishes the maximum potential length of a patent extension; the USPTO applies statutory limitations when calculating the actual extension. In its application, the applicant seeks 1,136 days of patent term extension (91 Fed. Reg. 64661-62).

Comment and petition windows

Anyone with knowledge that any of the published dates are incorrect may submit comments and ask for a redetermination by December 8, 2026, under 21 CFR 60.24. Any interested person may petition FDA under 21 CFR 60.30 for a determination whether the applicant for extension acted with due diligence during the regulatory review period, by April 7, 2027 (91 Fed. Reg. 64660, 64662).